I've done that before and it definitely can work.
Using the bus just isn't as much of a "sure thing" as the Monorail.
Just like the monorail, it might work. Buses often run about 20minutes apart. If your timing is lucky, you'll do fine. The drive takes 20minutes + 10min Epcot walk time =30min.
The BC bus will drop you off at the MK bus hub, not the TTC. If you have park hoppers, that's a better drop off. If you plan to watch the fireworks from the TTC- you'd need to get on the MK monorail.
Getting to see Both fireworks show is a bonus, not a promise. That's all I'm saying. It can work, via bus or monorail.
A taxi would be money well spent if this is important.
When our family attempts things like this, and the transportation is slow, we tend to get frustrated. That's big part of why we now consider a rental car a terrific value. I like the monorail, so even with a car, we often use it - but only when timing isn't important.
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The ferry is mostly slower than the monorail. You'd have some view of Wishes from the deck. Like all transportation though, much depends on timing.
For CR: 1.) if you are staying at CR, tower room MK side = great view. Love seeing Wishes from CR.
2.) if you have ADR at Cali Grill- see Wishes from Cali or 15th floor deck.
3.) if no to above, anyone can see Wishes from 4th floor deck.
However- If you take the BC bus to MK, it will drop you off at the bus hub. You then have to walk to CR plus take the elevator to the 4th floor) Or, walk to the monorail and take that over - probably walking directly to CR is faster from the bus depot. At a brisk pace, plan about 15min from the bus drop to the 4th floor deck.
Transportation to CR from Epcot is via double monorail: a.) Epcot monorail to TTC b.) transfer to resort monorail - and take it to the 4th stop
